Imagers and plate management

During a protein crystallization screen, literally thousands of experiments have to be carried out to find favorable crystallization conditions. Detecting crystals during these trials is challenging not only because of the sheer number of inspections required, but also because other factors—such as precipitates—can complicate analysis of the drops.

The Minstrel™ drop imager family

Minstrel family: Minstrel DT (left) and Minstrel HT (right)

Minstrel imagers, together with Gallery plate hotels/incubators, simplify the inspection and management of experimental plates with these unique approaches:

• Combined visible and UV inspections that dramatically reduce the time needed to analyze experiments
• Experimental plate management that can handle up to 1,380 plates — more gently than highly experienced lab technicians
• Software for management of experimental data and remote viewing capabilities of results included with each instrument
• Fully redundant temperature controlled incubation for high throughput applications

Inspections using visible and UV light

Complex drop imaged under visible (left) and UV (right) light

UV microscopy excites tryptophan and/or tyrosine residues in proteins and captures their fluorescence signals. Protein crystals produce significantly stronger signals than the solution, vastly increasing the possibility of detecting even small protein crystals in complex drops.

UV imaging requires specialized optics to produce images that have both high resolution and high contrast. The figure above shows a UV image of a needle shower taken with a Minstrel HT UV in which needles 2 μm in diameter could be easily resolved.

High resolution, high contrast UV images with the Minstrel HT UV

Minstrel drop imagers produce visible and UV images from a single optical train, creating a one-to-one correspondence between both images. This allows for unambiguous correlation between features, no matter whether they are observed under UV or visible light.

Managing protein crystallization plates

Protein crystallization labs typically deal with hundreds to thousands of plates at any given time. Minstrel imagers automatically generate inspections at specified intervals. In order to do so, they are coupled with Gallery plate hotels or incubators that act as plate management systems. The Galleries not only take care of plate storage, they are also responsible for delivering the plates to the imaging system.

The high throughput version, the Gallery HT, is equipped with temperature control between 4°C and 30°C. Each Minstrel HT imager can be combined with two Gallery HTs, which means that 1,380 plates incubated at two independent temperatures can be monitored by a single Minstrel HT imager. To fully protect your valuable experiments, the Gallery HT is equipped with two completely independent cooling systems together with software that monitors the operational state of both systems.

Software for data management and image analysis

CrystalTrak allows you to inspect your experimental results from any web browser. Click to enlarge.

Protein crystallization experiments can generate large amounts of data — especially when using automated imagers. The Minstrel imagers work together with CrystalTrak, a software system designed to take care of this flood of data automatically. CrystalTrak is also the main interface used to define inspection schedules and viewing imaging results. For Minstrel imagers configured to take combined UV and visible light images, CrystalTrak can be used to view both images exactly synchronized, allowing for simplified image analysis. When away from the office, a web enabled version of CrystalTrak, CT Web, allows inspection of results from any networked PC. 

Click here to learn more about CrystalTrak and here for a short video on image viewing and scoring.

Side-by-side comparison of functionality